Acting for Two: Besides playing his usual self in the beach party movies, Franke Avalon also plays British Invasion rocker/race car driver "The Potato Bug."
Fake Brit: American Frankie Avalon as the British "Potato Bug." Apparently the Beatles were just new and foreign enough then for him to play the part like Terry-Thomas on amphetamines.
What Could Have Been: Director William Asher claimed that the script was originally written for The Beatles. According to Asher's claim, the group had agreed to act in the film but later dropped out as their rapidly growing fame (especially after their 1964 appearance on The Ed Sullivan Show) caused their fee to exceed the film's budget. Asher was forced to rework the script, and Frankie Avalon's dual role as an English singer named "The Potato Bug" was created to replace the four Beatles in the story. That being said, it should be noted that United Artists had signed a three-movie deal with the Beatles in late 1963, which casts quite a bit of doubt on the veracity of Asher's claim.
While Yvonne, the "Lady Bug" is played by Danielle Aubry, her voice is dubbed over by an uncreditedElizabeth Montgomery, due to Aubry's thick French accent.